binutils-gdb/gdb/testsuite/gdb.python/py-recurse-unwind.py
Kevin Buettner 1a2f3d7ff1 Extend test gdb.python/py-recurse-unwind.exp
This patch modifies the unwinder (sniffer) defined in
py-recurse-unwind.py so that, depending upon the value of one of its
class variables, it will take different paths through the code,
testing different functionality.

The original test attempted to obtain the value of an undefined
symbol.

This somewhat expanded test checks to see if 'pc' can be read via
gdb.PendingFrame.read_register() and also via gdb.parse_and_eval().

gdb/testsuite/ChangeLog:

	* gdb.python/py-recurse-unwind.c (main): Add loop.
	* gdb.python/py-recurse-unwind.py (TestUnwinder): Add calls
	to read_register() and gdb.parse_and_eval().  Make each code
	call a separate case that can be individually tested.
	* gdb.python/py-recurse-unwind.exp (cont_and_backtrace): New
	proc. Call cont_and_backtrace for each of the code paths that
	we want to test in the unwinder.
2016-11-16 11:37:11 -07:00

88 lines
2.7 KiB
Python

# Copyright (C) 2016 Free Software Foundation, Inc.
# This program is free software; you can redistribute it and/or modify
# it under the terms of the GNU General Public License as published by
# the Free Software Foundation; either version 3 of the License, or
# (at your option) any later version.
#
# This program is distributed in the hope that it will be useful,
# but WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
# GNU General Public License for more details.
#
# You should have received a copy of the GNU General Public License
# along with this program. If not, see <http://www.gnu.org/licenses/>.
# This unwinder never does any unwinding. It'll (pretend to) "sniff"
# the frame and ultimately return None, indicating that actual unwinding
# should be performed by some other unwinder.
#
# But, prior to returning None, it will attempt to obtain the value
# associated with a symbol via a call to gdb.parse_and_eval(). In
# the course of doing this evaluation, GDB will potentially access
# some frames, leading to the possibility of a recursive invocation of
# this unwinder. If that should happen, code contained herein detects
# that and prints a message which will cause some of the associated
# tests to FAIL.
import gdb
from gdb.unwinder import Unwinder
class TestUnwinder(Unwinder):
count = 0
@classmethod
def reset_count (cls):
cls.count = 0
@classmethod
def inc_count (cls):
cls.count += 1
test = 'check_undefined_symbol'
@classmethod
def set_test (cls, test) :
cls.test = test
def __init__(self):
Unwinder.__init__(self, "test unwinder")
self.recurse_level = 0
def __call__(self, pending_frame):
if self.recurse_level > 0:
gdb.write("TestUnwinder: Recursion detected - returning early.\n")
return None
self.recurse_level += 1
TestUnwinder.inc_count()
if TestUnwinder.test == 'check_user_reg_pc' :
pc = pending_frame.read_register('pc')
pc_as_int = int(pc.cast(gdb.lookup_type('int')))
# gdb.write("In unwinder: pc=%x\n" % pc_as_int)
elif TestUnwinder.test == 'check_pae_pc' :
pc = gdb.parse_and_eval('$pc')
pc_as_int = int(pc.cast(gdb.lookup_type('int')))
# gdb.write("In unwinder: pc=%x\n" % pc_as_int)
elif TestUnwinder.test == 'check_undefined_symbol' :
try:
val = gdb.parse_and_eval("undefined_symbol")
except Exception as arg:
pass
self.recurse_level -= 1
return None
gdb.unwinder.register_unwinder(None, TestUnwinder(), True)
gdb.write("Python script imported\n")